Propagation-medium-modification-based reverberated-signal elimination

Abstract

Acquired echo data is corrected to reduce content from ultrasound that has undergone at least one reflection off the probe surface, for example, to reduce corresponding reverberation artefacts from imaging. In some embodiments, the propagation medium, i.e., layer or adjoining layers, through which the reverberation occurs, is, after a set of echo radiofrequency data ( 404, 408 ) has been acquired, modified in preparation for a next application of ultrasound. During that next application, it is the reverberating ultrasound signals ( 424 ), according to embodiments of the invention, that are more affected by the modification than are the non-reverberating, i.e., direct signals ( 420 ). This difference in effect is due, for example, to greater overall time of flight through the modified medium on account of reverberation in the propagation path.

1 . An ultrasound apparatus ( 200 ) configured for, in correcting a set of echo radiofrequency data acquired from a propagation path through a propagation medium, taking into account at least one other set of echo radiofrequency data received from the propagation medium so as to reduce content from signals that reverberated through said medium, said set and said at least one other set all differing due to respective axially modifying the propagation path of said medium. 
     
     
         2 . The apparatus of  claim 1 , wherein said correcting comprises combining, with said set to be corrected, said at least one other set. 
     
     
         3 . The apparatus of  claim 2 , the reducing being performed by counterbalancing said content. 
     
     
         4 . The apparatus of  claim 3 , said counterbalancing being against data of magnitude equal to that of said content. 
     
     
         5 . The apparatus of  claim 2 , said combining comprising time-shifting a set, from among the sets to be combined, by λ/2, λ representing wavelength. 
     
     
         6 . The apparatus of  claim 2 , the data to be combined, in said combining, being at least one of per-channel data and beam-summed data. 
     
     
         7 . (canceled) 
     
     
         8 . The apparatus of  claim 2 , said combining comprising deriving images from the sets to be combined and averaging the derived images. 
     
     
         9 . (canceled) 
     
     
         10 . The apparatus of  claim 1 , comprising a wearable headpiece, said headpiece having an inside and being configured for supporting an ultrasound probe and for mobility of said probe at least one of toward and away from said inside in performance of said modifying. 
     
     
         11 . (canceled) 
     
     
         12 . (canceled) 
     
     
         13 . The apparatus of  claim 1 , said modifying causing effective propagation length to change. 
     
     
         14 . The apparatus of  claim 1 , said taking into account comprising making, based on results of comparison between a pair of sets from among said set and said at least one other set, a mask for selectively excluding part of an image. 
     
     
         15 . The apparatus of  claim 1 , said modifying comprising introducing an offset to a length of a propagation path, said offset being λ/4n, λ representing wavelength, “n” being an integer that is positive or negative. 
     
     
         16 . The apparatus of  claim 15 , n being equal to 1 or −1. 
     
     
         17 . The apparatus of  claim 1 , said modifying comprising at least one of inserting and removing ultrasound attenuating material. 
     
     
         18 . The apparatus of  claim 1 , said modifying comprising translating an ultrasound probe axially. 
     
     
         19 . (canceled) 
     
     
         20 . A data correction method for correcting for reverberation artifacts in echo signals received by an ultrasound probe comprising:
 acquiring a set of echo radiofrequency data from a propagation medium;   performing one or more times in sequence the acts of modifying said medium by axial change of a propagation path through the propagation medium and then acquiring a set of echo radiofrequency data; and,   in correcting a set from among the acquired sets, taking into account at least one other of the acquired sets to reduce imaging artifacts arising due to reverberation that has occurred through said medium.   
     
     
         21 . The method of  claim 20 , further comprising, before the act of acquiring from the modified medium, the act of, in compensation for said modifying, offsetting a delay in said acquiring from the modified medium. 
     
     
         22 . The method of  claim 20 , said modifying comprising translating an ultrasound probe axially, said translating comprising imparting a jitter to said probe. 
     
     
         23 . The method of  claim 20 , ultrasound to undergo said reverberation being pulsed and bandwidth-limited, a distance between a pair of locations of an ultrasound probe axially-translated in said modifying being larger than a threshold representing half the bandwidth-limited axial resolution. 
     
     
         24 .- 25 . (canceled)